1. Field of the Invention
The present invention relates to ligands, transition metal complexes thereof and enantioselective processes based on the reactions of these complexes for forming a product with an enantiomeric excess of an optical isomer. More specifically, the present invention relates to chiral 2,2xe2x80x2-substituted-1,1xe2x80x2-binaphthyl ligands, Pd, Rh, Ru, Ir, Cu, Ni, Mo, Ti, V, Re and Mn complexes thereof and enantioselective processes based on hydrogenation, hydroformylation, allylic alkylation, cyclopropanation, Heck, Aldol, Michael addition and epoxidation reactions of these complexes to form an enantiomerically enriched product.
2. Description of the Prior Art
Design and synthesis of new chiral ligands play a crucial role in the development of transition metal-catalyzed asymmetric reactions. The symmetric (e.g., BINAP, Noyori, R.; Takaya, H. Acc. Chem. Res. 1990, 23, 345) and unsymmetrical (e.g., MOP, Uozumi, Y.; Hayashi, T. J. Am. Chem. Soc. 1991, 113, 9887) binaphthyl scaffolds have been demonstrated as effective ligands for a variety of asymmetric reactions. 
Chiral 2-amino-2xe2x80x2-hydroxy-1,1xe2x80x2-binaphthyl (NOBIN) developed by Kocovsky et al. has proven to be an excellent framework for constructing chiral ligands to conduct asymmetric catalytic reactions (see M. Smrcina et al., Synlett., 1991, 231; S. Vyskocil et al., J. Org. Chem., 1998, 63, 7727; and S. Vyskocil, J. Org. Chem., 1998, 63, 7738).
Various synthetic routes and resolution methods for synthesizing NOBIN in large quantities have been tried (see M. Smrcina et al., Collect. Czech. Chem. Commun., 1996, 61, 1520 and K. Ding et al., J. Chem. Soc., Chem. Commun., 1997, 693). One of the most notable applications has been the use of NOBIN as the chiral backbone in Carreira""s chiral aldol catalyst (see E. M. Carreira et al., J. Am. Chem. Soc., 1994, 116, 8837; E. M. Carreira et al., J. Am. Chem. Soc., 1995, 117, 3649 and R. A. Singer et al., J. Am. Chem. Soc., 1995, 117, 12360).
Several chiral ligands that are described in the prior art are summarized below. 
None of the above references disclose the ligands according to the present invention and the highly enantioselective transition metal catalysts derived therefrom that are useful in effecting a variety of enantioselective chemical transformations.
It is an object of the present invention to develop new chiral ligands and new chiral catalysts based on such chiral ligands that are useful in the preparation of asymmetric products via enantioselective reactions.
Accordingly, the present invention includes families of chiral ligands based on 2-amino-2xe2x80x2-hydroxy-1,1xe2x80x2-binaphthyl and related frameworks for asymmetric catalysis. Transition metal complexes of these ligands can be used as catalysts for a variety of asymmetric reactions such as hydrogenation, hydroformylation, Michael addition, Heck reaction, Aldol reaction, allylic alkylation, cyclopropanation, epoxidation, olefin metathesis and other reactions.
An optically active or racemic ligand selected from the group consisting of compounds represented by A through H; wherein A is represented by the formula selected from the group consisting of: 
wherein each R is independently selected from the group consisting of: alkyl, aryl, substituted aryl, aralkyl and substituted aralkyl; each of X and Y is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; and Ar is an aryl group;
wherein B is represented by the formula selected from the group consisting of: 
xe2x80x83wherein each of R and Rxe2x80x2 is independently selected from the group consisting of: alkyl, aryl and aralkyl; X is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; each Rxe2x80x3 is independently selected from the group consisting of: H, alkyl, substituted alkyl, aryl, substituted aryl, 1,2-, 1,3- or 1,4-arylene, and a group that is part of an aryl system; Z is selected from the group consisting of: (CH2)n wherein n is 0, 1 or 2, CR2 wherein R is alkyl or aryl, aryl, substituted aryl, heteroaryl, phenol and aryl carboxylate;
wherein C is represented by the formula selected from the group consisting of: 
xe2x80x83wherein each Y is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; each Rxe2x80x3 is independently selected from the group consisting of: H, alkyl, substituted alkyl, aryl, substituted aryl, 1,2-, 1,3- or 1,4-arylene, and a group that is part of an aryl system; Z is selected from the group consisting of: (CH2)n wherein n is 0, 1 or 2, CR2 wherein R is alkyl or aryl, aryl, substituted aryl, heteroaryl, phenol and aryl carboxylate; and each A is independently selected from the group consisting of: H, alkyl and substituted alkyl;
wherein D is represented by the formula selected from the group consisting of: 
xe2x80x83wherein each Y is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; each Rxe2x80x3 is independently selected from the group consisting of: H, alkyl, substituted alkyl, aryl, substituted aryl, and a group that is part of an aryl system; S is independently selected from the group consisting of: (CH2)n wherein n is 2-6 and CH2(Ar)CH2 wherein Ar is arylene or substituted arylene; and each A is independently selected from the group consisting of: H, alkyl and substituted alkyl;
wherein E is represented by the formula selected from the group consisting of: 
xe2x80x83wherein each X and Y is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; Z is selected from the group consisting of: (CH2)n wherein n is 0, 1 or 2, CR2 wherein R is alkyl or aryl, aryl, 1,2-, 1,3- or 1,4-arylene, substituted aryl, heteroaryl, phenol and aryl carboxylate; and each A is independently selected from the group consisting of: H, alkyl and substituted alkyl;
wherein F is represented by the formula selected from the group consisting of: 
xe2x80x83wherein each Y is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; V is independently selected from the group consisting of: alkyl, aryl, substituted alkyl and substituted aryl; and A is independently selected from the group consisting of: H, alkyl and substituted alkyl;
wherein G is represented by the formula selected from the group consisting of: 
xe2x80x83wherein V is independently selected from the group consisting of: alkyl, aryl, substituted alkyl and substituted aryl; and Z is independently selected from the group consisting of: (CH2)n wherein n is 0, 1 or 2, CR2 wherein R is alkyl or aryl, aryl, 1,2-, 1,3- or 1,4-arylene, substituted aryl, heteroaryl, phenol, ferrocene and aryl carboxylate; and
wherein H is represented by the formula selected from the group consisting of: 
xe2x80x83wherein each Y is independently selected from the group consisting of: H, one or more halide, alkyl, aryl, alkoxide, nitro and carboxylate; each Rxe2x80x3 is independently selected from the group consisting of: H, alkyl, substituted alkyl, aryl, substituted aryl, and a group that is part of an aryl system; and A is independently selected from the group consisting of: H, alkyl and substituted alkyl.
The present invention further includes a catalyst prepared by a process comprising contacting a transition metal salt, or a complex thereof, and a ligand according to the present invention.
The present invention still further includes a process for preparation of an asymmetric compound. The process comprises contacting a substrate capable of forming an asymmetric product by an asymmetric reaction and a catalyst according to the present invention.
The present invention also includes a process for the synthesis of chiral 2-amino-2xe2x80x2-hydroxy-1,1xe2x80x2-binaphthyl. The process comprises contacting 1,1xe2x80x2-bi-2-naphthol (2,2xe2x80x2-dihydroxy-1,1xe2x80x2-binaphthyl) and (NH4)2SO3H2O at a temperature and length of time sufficient to produce 2-amino-2xe2x80x2-hydroxy-1,1xe2x80x2-binaphthyl.